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Tutorlal-GBS
Neurology tutorial 07/12/12- Guillain-Barre Syndrome NUS YLLSOM Year 3 CG 21 - Clinical features of GBS o Lost of reflexes § Reflexes is the modality that is first lost because it involves a fast CONDUCTION HIGHLY MYELINATED circuit § Distal > proximal o Distal +/- prox weakness o Peripheral neuropathy involving cranial nerves – think of GBS, especially if multiple CNs are affected at the same time § DDx: DM neuropathy - but affects one nerve at each time & a/w long-standing history of diabetes § Note: sensory loss may be patchy o Diagnostic criteria § Requires progressive weakness of >1 limb/trunk/facial/extra-ocular/bulbar muscles and areflexia (distal predominant) § Supportive features: clinical course (peaking @ 3 weeks) and typical CSF/NCS findings - Investigations o Nerve conduction studies o Spinal tap: CSF profile § Albuminocytologic dissociation i.e. elevated CSF protein with normal/mildly elevated CSF WBC count – occurs 1 week after symptom onset · Note: protein levels may not be raised on 10% of pts · Proteins are raised because of increased permeability @ blood-CSF and blood-nerve barrier and widespread inflammation + demyelination of peripheral nerves and nerve roots · WBC not raised as GBS is not due to infection (c.f. meningitis) § If CSF cell count is high – consider concurrent HIV infection OR alternative diagnosis GOOD o Others: FBC, UECr, PT, aPTT to assess general status of patient § Also to assess for any contraindication to a spinal tap - Acute management of GBS o Assess breathing § SpO2: less useful as type II respiratory failure occurs (hypercapnia) · Safe cut-off: 95% on room air § Arterial blood gas: looking for hypercapnia § Forced vital capacity and negative inspiratory force (NIF) (also used as non-invasive monitoring tools) o Swallowing should be assessed early and continue surveillance – to facilitate feeding/taking of medications (refer to below) - Definitive management of GBS o IV immunoglobulin o Plasma exchange - General/supportive management of GBS – to prevent complications o Swallowing § Methods: Bedside swallowing test vs speech therapist swallowing assessment vs video fluroscopic swallowing exam § Decide on consistency of diet / need for nasogastric tube feeding § Prevent aspiration pneumonia by nursing at 30 degrees + chest physiotherapy o Assess for early signs of Type 2 respiratory failure – (hypercapnia) § ABG initially § Monitor for using FVC and NIF – ABG if required § May require intubation and ventilation (increased likelihood if pt has bulbar weakness and/or severe weakness e.g. unable to cough) o Autonomic involvement § Postural hypotension · Monitor – postural BP charting BD § Ileus · Monitor for by listening for bowel sounds, IO charting · Prevent by minimizing opioid adminsitration · May require pharmacological help § Acute retention of urine · Monitor – IO charting, post-void residual urine (PVRU) · Prevent complications of ARU – reflux nephropathy or UTI (clear bowels) · May require IDC insertion or clean-intermittent catetherization § Arrhythmias o Complications of immobilization § Prevent pressure sores – frequent turning, alternative pressure mattress § Prevent deep vein thrombosis · Ensure hydration – IV drip if required if not taking well orally · TED stockings · Cuff pumps · Prophylaxis: subcut clexane o Higher likelihood if weakness severe i.e. power < 3 out of 5 § Prevent entrapment neuropathies and contractures · Physiotherapy and occupational therapy +/- use of splints